In LBRV tests, failures in the guest trigger a #UD and does not convey
useful debugging info (i.e. expected and actual values of MSRs). Replace
them with proper report() calls.
Admittedly, it is unclear why the choice of #UD was made given that
report() works fine in the guest.
Signed-off-by: Yosry Ahmed <yosry.ahmed@linux.dev>
---
x86/svm_tests.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)
diff --git a/x86/svm_tests.c b/x86/svm_tests.c
index 2981f459032cb..8d309860e76e5 100644
--- a/x86/svm_tests.c
+++ b/x86/svm_tests.c
@@ -3017,16 +3017,17 @@ do { \
TEST_EXPECT_EQ((u64)to_expected, amd_get_lbr_rip(MSR_IA32_LASTBRANCHTOIP)); \
} while (0)
-/*
- * FIXME: Do something other than generate an exception to communicate failure.
- * Debugging without expected vs. actual is an absolute nightmare.
- */
#define GUEST_CHECK_LBR(from_expected, to_expected) \
do { \
- if ((u64)(from_expected) != amd_get_lbr_rip(MSR_IA32_LASTBRANCHFROMIP)) \
- asm volatile("ud2"); \
- if ((u64)(to_expected) != amd_get_lbr_rip(MSR_IA32_LASTBRANCHTOIP)) \
- asm volatile("ud2"); \
+ u64 from_ip = amd_get_lbr_rip(MSR_IA32_LASTBRANCHFROMIP); \
+ u64 to_ip = amd_get_lbr_rip(MSR_IA32_LASTBRANCHTOIP); \
+ \
+ report((u64)(from_expected) == from_ip, \
+ "Expected MSR_IA32_LASTBRANCHFROMIP: 0x%lx, found: 0x%lx", \
+ (u64)from_expected, from_ip); \
+ report((u64)(to_expected) == to_ip, \
+ "Expected MSR_IA32_LASTBRANCHTOIP: 0x%lx, found: 0x%lx", \
+ (u64)to_expected, to_ip); \
} while (0)
#define REPORT_GUEST_LBR_ERROR(vmcb) \
--
2.51.2.1026.g39e6a42477-goog